function [ r ] = conv_point( fin, k, point )

if (size(fin, 1) ~= 1)
    error('bad fin size');
end

if (size(k, 1) ~= 1)
    error('bad k size');
end

if (point < 1)
    error('bad point index');
end

if (point > size(fin, 2))
    error('bad point index');
end

s1 = size(fin, 2);
s2 = size(k, 2);

L = fix(size(k,2)/2)+1;
H = L + size(fin, 2) - 1;

m = point + L - 1;

fin1 = max(m-s2+1, 1);
fin2 = min(m, s1);
k1 = max(m-s1+1, 1);
k2 = min(m, s2);
r = sum(fin(fin1:fin2) .* k(k2:-1:k1));

end



